Heat dissipating base structure

ABSTRACT

A heat dissipating base structure includes a base; a plurality of heat dissipating fins disposed on the base and arranged in parallel to each other, each of the heat dissipating fins being formed with at least a first through hole and a second through hole corresponding to the first through hole; and at least a U-shaped heat pipe having a bending portion and two pipe leg portions extending from two ends of the bending portion respectively. The cross section of the pipe leg portions is smaller than the size of the first and second through holes. Each of the pipe leg portions is fixedly disposed in the first and second through holes at one side thereof respectively, and can move freely in the holes before being fixedly disposed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to heat dissipating basestructures, and more particularly, to a heat dissipating base structurehaving a U-shaped heat pipe.

2. Description of Related Art

In a conventional heat dissipating base having a heat pipe, in order tosolder the heat pipe to a plurality of heat dissipating fins of the heatdissipating base, a dispensing process comprising the following steps isperformed: first, a groove or a hole is formed on an upper side of heatpipe holes of the heat dissipating fins, wherein the heat pipe isinserted into the heat dissipating fins through the heat pipe holes;then, a dispensing tip is inserted into the groove or the hole so as todispense solder paste between the heat pipe and the heat dissipatingfins, the solder paste at a melting state further flows through thespacing between the heat pipe and the heat dissipating fins bygravitational force and capillary force, thereby filling space betweenthe heat pipe and the heat dissipating fins. However, the natural draindown of the solder paste cannot ensure the heat pipe and the heatdissipating fins are completely soldered together. If the heat pipe andthe heat dissipating fins are not completely soldered together, the heattransfer effect from the heat pipe to the heat dissipating fins will beadversely affected, which further adversely affects the heat dissipatingefficiency of the heat dissipating base.

Referring to FIGS. 1A and 1B, a conventional heat dissipating basehaving a heat pipe comprises a base 10; a plurality of heat dissipatingfins 11 disposed on the base 10 and arranged in parallel to each other,each of the heat dissipating fins 11 having a plurality of heat pipeholes 110; and a U-shaped heat pipe 20 having two pipe legs insertedinto the heat pipe holes 110 of the heat dissipating fins 11. On theupper side of the heat pipe holes 110 there are disposed openings 111 asshown in FIG. 1A or grooves 112 as shown in FIG. 1B such that adispensing tip (not shown) can be inserted into inside of the heatdissipating fins 11 through the openings 111 or the grooves 112 fordispensing. As shown in FIG. 2A, after a dispensing process is performedto the structure of FIG. 1B, the solder paste 21 is attached to theU-shaped heat pipe 20. Subsequently, the whole heat dissipating basestructure is put into an oven such that the solder paste 21 can bemelted. The melted solder paste 21 further flows through and fillsspacing between the heat pipe 20 and the heat pipe holes 110 of the heatdissipating fins 11 by gravitational force and capillary force, therebysoldering together the U-shaped heat pipe 20 and the heat dissipatingfins 11.

However, the natural drain down of the solder paste 21 cannot ensure theheat pipe and the heat dissipating fins are completely solderedtogether. As shown in FIG. 2B, spacing between the lower portion of theU-shaped heat pipe 20 and the heat pipe hole 110 of the heat dissipatingfins 11 is not filled with the solder paste 21, which can adverselyaffect the heat transfer effect from the heat pipe 20 to the heatdissipating fins 11 and the heat dissipating effect of the heatdissipating base. Further, since the diameter of the heat pipe holes 110corresponds to the diameter of the U-shaped heat pipe 20, once theU-shaped heat pipe 20 is inserted into the heat pipe holes 110, theU-shaped heat pipe 20 cannot make any displacement. Therefore, it is notpossible to perform a dispensing process to the lower pipe leg of theU-shaped heat pipe 20. Correspondingly, an opening or a groove similarto the above-mentioned opening or groove also needs to be formed forallowing a dispensing tip to enter into inside of the heat dissipatingfins such that the lower pipe leg can be soldered to the heatdissipating fins. However, in the prior art, no such opening or grooveis formed taking into account of such factors as heat dissipating area.Instead, the lower pipe leg of the U-shaped heat pipe 20 is keptseparated from the heat dissipating fins 11, which thus leads to a poorheat conduction therebetween and accordingly reduces the heatdissipating effect of the heat dissipating base.

Therefore, how to overcome the above drawback has become urgent.

SUMMARY OF THE INVENTION

According to the above drawbacks, an objective of the present inventionis to provide a heat dissipating base structure having elliptic throughholes such that a heat pipe of the heat dissipating base structure canhave a certain displacement freedom during a soldering process of theheat pipe, thereby facilitating the soldering process of the heat pipeand saving soldering time.

Another objective of the present invention is to provide a heatdissipating base structure with heat pipe having good soldering effect.

A further objective of the present invention is to provide a heatdissipating base structure having improved heat dissipating efficiency.

In order to attain the above and other objectives, the present inventiondiscloses a heat dissipating base structure, comprising: a base; aplurality of heat dissipating fins arranged in parallel and disposed onthe base, each of the fins having at least a first through hole and asecond through hole corresponding to the first through hole; and atleast a U-shaped heat pipe having a bending portion and two pipe legportions extending from two ends of the bending portion, wherein, thecross section of the pipe leg portions is smaller than the size of thefirst and second through holes, the pipe leg portions are inserted intothe first and second through holes and fixedly disposed to one side ofthe first and second through holes respectively, before being fixedlydisposed, the pipe leg portions can freely move in the first and secondthrough holes.

Preferably, the first and second through holes are elliptic. The firstand second through holes can be arranged in a line perpendicular to ahorizontal line. Alternatively, the first and the second through holesare arranged in a horizontal line. The U-shaped heat pipe is fixed toone side of the first and second through holes by a conductive materialthrough a soldering method. The conductive material is one of gold,silver, solder paste, and a mixture of at least two thereof.

Compared with the prior art that solders the heat pipe and the heatdissipating fins together by forming little through holes for insertingof a dispensing tip so as to dispense the solder material and make thesoldering material fill the spacing between the heat pipe and the heatdissipating fins through the gravitational force of the solder materialand capillary force formed in the spacing between the heat pipe and theheat dissipating fins, the present invention provides elliptic throughholes for a heat dissipating base structure such that heat pipe of theheat dissipating base structure can have a certain displacement freedomin the through holes. Thus, the position of the heat pipe can beadjusted for a dispensing process. Then through an external force, theheat pipe can be pressed to closely contact and fixedly soldered to oneside of the through holes so as to obtain a good soldering effectbetween the heat pipe and the heat dissipating fins. Thereby, the heatconducting effect between the heat pipe and the heat dissipating fins isimproved and further the heat dissipating efficiency of the whole heatdissipating base structure is improved.

Therefore, the heat dissipating base structure of the present inventionovercomes the drawbacks of the prior art, obtains a good solderingeffect, saves the time required for the soldering process and improvesthe heat dissipating efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a diagram of a conventional heat dissipating base structurehaving holes formed for insertion of a dispensing tip;

FIG. 1B is a diagram of a conventional heat dissipating base structurehaving grooves formed for inserting of a dispensing tip;

FIG. 2A is a partially expanded diagram showing a state after solderpaste is dispensed to the structure of FIG. 1B;

FIG. 2B is a partially expanded diagram showing a soldering statebetween the heat pipe and the heat dissipating fins of the heatdissipating base structure of FIG. 2A;

FIG. 3 is a diagram of a heat dissipating base structure according to afirst embodiment of the present invention;

FIG. 4A is a diagram showing a state of the heat dissipating basestructure of FIG. 3 before heat pipe is soldered to the heat dissipatingfins;

FIG. 4B is a diagram showing a state of the heat dissipating basestructure of FIG. 3 after heat pipe is soldered to the heat dissipatingfins;

FIG. 5 is a diagram of a heat dissipating base structure according to asecond embodiment of the present invention;

FIG. 6A is a diagram showing a state of the heat dissipating basestructure of FIG. 5 before heat pipe is soldered to the heat dissipatingfins;

FIG. 6B is a diagram showing a state of the heat dissipating basestructure of FIG. 5 after heat pipe is soldered to the heat dissipatingfins;

FIG. 7 is a diagram of a heat dissipating base structure according to athird embodiment of the present invention;

FIG. 8A is a diagram showing a state of the heat dissipating basestructure of FIG. 7 before heat pipe is soldered to the heat dissipatingfins; and

FIG. 8B is a diagram showing a state of the heat dissipating basestructure of FIG. 7 after heat pipe is soldered to the heat dissipatingfins.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following illustrative embodiments are provided to illustrate thedisclosure of the present invention, these and other advantages andeffects can be apparent to those skilled in the art after reading thedisclosure of this specification. The present invention can also beperformed or applied by other different embodiments. The details of thespecification may be on the basis of different points and applications,and numerous modifications and variations can be made without departingfrom the spirit of the present invention.

FIG. 3 shows a heat dissipating base structure according to a firstembodiment of the present invention. The heat dissipating base structurecomprises a base 30 having a surface 31; a plurality of heat dissipatingfins 40 disposed on the surface 31 of the base 30 and arranged inparallel to each other, each of the heat dissipating fins 40 having twoelliptic first through holes 41 and two elliptic second through holes 42corresponding to the first through holes 41 and disposed at an edge sideof the heat dissipating fins 40 bonded with the base 30, the first andsecond through holes being arranged in a line perpendicular to ahorizontal line; two U-shaped heat pipes 50 each having a bendingportion 52 and two pipe leg portions 51 extending from two ends of thebending portion 52, the pipe leg portions 51 having a cross sectionsmaller than sizes of the first through holes 41 and the second throughholes 42. The pipe leg portions 51 are inserted into the first andsecond through holes 41, 42 respectively and fixed to an upper side ofthe first and second through holes 41, 42 by a conductive material suchas solder paste 60. Alternatively, the conductive material can be one ofgold, silver, solder paste or a mixture of at least two thereof.

Referring to FIGS. 4A and 4B, a solder paste 60 is dispensed to the twopipe leg portions 51 of the U-shaped heat pipes 50, respectively. Asshown in FIG. 4A, the pipe leg portions 51 of the U-shaped heat pipes 50are not in contact with the upper sides of the first and second throughholes 41, 42, and the base 30 is separated from the heat dissipatingfins 40. While the base 30 is soldered together with the heatdissipating fins 40, the U-shaped heat pipes 50 are pressed upward suchthat the pipe leg portions 51 of the heat pipes 50 can be closely incontact with the upper sides of the first and second through holes 41,42, respectively. If the bending portions 52 of the U-shaped heat pipes50 lack sufficient strength and are not capable of keeping the upperpipe leg portions 51 to be closely in contact with the upper sides ofthe first through holes 41, a tool such as an iron pipe can be insertedto the spacing between the upper pipe leg portions 51 and the lowerportion of the first through holes 41 so as to press the upper pipe legportions 51 upward and make the upper pipe leg portions 51 closelycontact the upper side of the first through holes 41, thereby improvingthe soldering effect of the solder paste 60 on the pipe leg portions 51.As a result, the heat dissipating efficiency of the heat dissipatingbase structure can be improved.

FIG. 5 shows a heat dissipating base structure according to a secondembodiment of the present invention. The heat dissipating base structurecomprises a base 30 having a surface 31; a plurality of heat dissipatingfins 40 stacked on the surface 31 of the base 30 and arranged inparallel to each other, each of the heat dissipating fins 40 having anelliptic first through hole 41 and an elliptic second through hole 42corresponding to the first through hole 41, the first and second throughholes being horizontally arranged, the first and second through holes41, 42 having their major axes perpendicular to the horizontal line; anda U-shaped heat pipe 50 having a bending portion 52 and two pipe legportions 51 extending from two ends of the bending portion 52, thebending portion 52 being soldered together with the base 30, the pipeleg portions 51 having a cross section smaller than the size of thefirst through hole 41 and the second through hole 42. The pipe legportions 51 are inserted into the first through hole 41 and the secondthrough hole 42 and fixed to an upper side of the first and secondthrough holes 41, 42 by a conductive material such as solder paste 60.Alternatively, the conductive material can be one of gold, silver,solder paste or a mixture of at least two thereof.

Referring to FIGS. 6A and 6B, solder paste 60 is dispensed to the twopipe leg portions 51 of the U-shaped heat pipes 50, respectively. Asshown in FIG. 6A, the pipe leg portions 51 of the U-shaped heat pipe 50are not in contact with the upper sides of the first and second throughholes 41, 42. Then, an iron pipe is inserted into the spacing betweenthe pipe leg portions 51 and the lower portions of the first and secondthrough holes 41, 42 so as to press the pipe leg portions 51 upward andmake the pipe leg portions 51 closely contact the upper sides of thefirst and second through holes 41, 42, respectively, as shown in FIG.6B, thereby improving the soldering effect of the solder paste 60 on thepipe leg portions 51. As a result, the heat conducting effect isimproved, and further the heat dissipating efficiency of the heatdissipating base structure is improved.

FIG. 7 is a diagram showing a heat dissipating base structure accordingto a third embodiment of the present invention. The heat dissipatingbase structure comprises a base 30 having a surface 31; a plurality ofheat dissipating fins 40 stacked on the surface 31 of the base 30 andarranged in parallel to each other, each of the heat dissipating fins 40having an elliptic first through hole 41 and an elliptic second throughhole 42 corresponding to the first through hole 41, the first and secondthrough holes being horizontally arranged, the first and second throughholes 41, 42 having their major axes arranged in a horizontal line; anda U-shaped heat pipe 50 having a bending portion 52 and two pipe legportions 51 extending from two ends of the bending portion 52, thebending portion 52 being soldered together with the base 30, the pipeleg portions 51 having a cross section smaller than the size of thefirst through hole 41 and the second through hole 42. The pipe legportions 51 are inserted into the first and second through holes 41, 42respectively and fixed to one side of the first and second through holes41, 42 by a conductive material such as solder paste 60. In the presentembodiment, the pipe leg portions 51 are fixed to a left side of thefirst and second through holes 41, 42 respectively. Alternatively, theconductive material can be one of gold, silver, solder paste or amixture of at least two thereof.

Referring to FIGS. 8A and 8B, solder paste 60 is dispensed to the twopipe leg portions 51 of the U-shaped heat pipes 50, respectively. Asshown in FIG. 8A, the pipe leg portions 51 of the U-shaped heat pipe 50are not in contact with the left sides of the first and second throughholes 41, 42. Then, an iron pipe is inserted to the spacing between thepipe leg portions 51 and right sides of the first and second throughholes 41, 42 so as to press the pipe leg portions 51 leftward and makethe pipe leg portions 51 closely contact the left sides of the first andsecond through holes 41, 42, thereby improving the soldering effect ofthe solder paste 60 on the pipe leg portions 51. As a result, the heatconducting effect is improved, and further the heat dissipatingefficiency of the heat dissipating base structure is improved.

Compared with the prior art, the present invention provides ellipticthrough holes for a heat dissipating base structure such that a heatpipe of the heat dissipating base structure can have a certaindisplacement freedom in the through holes. Thus, the position of theheat pipe can be adjusted for a dispensing process. Then through anexternal force, the heat pipe can be pressed to closely contact andfixedly soldered to one side of the through holes so as to obtain a goodsoldering effect between the heat pipe and the heat dissipating fins.Thereby, the heat conducting effect between the heat pipe and the heatdissipating fins is improved and further the heat dissipating efficiencyof the whole heat dissipating base structure is improved.

Therefore, the heat dissipating base structure of the present inventionovercomes the drawbacks of the prior art, obtains a good solderingeffect, saves the time required for the soldering process and improvesthe heat dissipating efficiency.

The above-described descriptions of the detailed embodiments are only toillustrate the preferred implementation according to the presentinvention, and it is not to limit the scope of the present invention,Accordingly, all modifications and variations completed by those withordinary skill in the art should fall within the scope of presentinvention defined by the appended claims.

1. A heat dissipating base structure, comprising: a base; a plurality ofheat dissipating fins disposed on the base and arranged in parallel toeach other, each of the heat dissipating fins having at least a firstthrough hole and a second through hole corresponding to the firstthrough hole; and at least a U-shaped heat pipe having a bending portionand two pipe leg portions extending from two ends of the bendingportion, the pipe leg portions having a cross section smaller than sizesof the first and second through holes and being inserted into the firstand second through holes and fixedly disposed to one side of the firstand second through holes respectively, the pipe leg portions, when notbeing fixedly disposed, capable of freely moving in the first and secondthrough holes.
 2. The heat dissipating base structure of claim 1,wherein the first through hole is elliptic.
 3. The heat dissipating basestructure of claim 1, wherein the second through hole is elliptic. 4.The heat dissipating base structure of claim 1, wherein the first andsecond through holes are arranged in a line perpendicular to ahorizontal line.
 5. The heat dissipating base structure of claim 1,wherein the first and the second through holes are arranged in ahorizontal line.
 6. The heat dissipating base structure of claim 1,wherein the U-shaped heat pipe is fixed to one side of the first andsecond through holes by a conductive material through a solderingmethod.
 7. The heat dissipating base structure of claim 6, wherein theconductive material is one of gold, silver, solder paste, and a mixtureof at least two thereof.